Based on the theory of particle flow code (PFC)

one of the discrete element methods

a series of biaxial tests are simulated to establish the relationship between micro parameters and macro mechanical properties. A numerical model of similar soil slope with weak intercalated layer is constituted by adopting the parallel-bond model of PFC. The progressive failure process of slope is simulated and fissures in slope are monitored during excavation. The simulation results show that the failure experiences a process of fissures formed

grew lager

and developed until large scale landslide occurs. The fissures form from the toe of the slope and weak intercalated layer at first

then expanded until slide occurs

which behaves as a typical progressive failure process; soil structure is seriously damaged and bearing capacity decline after slide occurs. The simulated failure process and numerical results fit the site condition well. It is shown that the proposed method can be used to study the similar soil slope’s failure process and its mechanism.